Screening mechanism



' Oct. 2, 1928.

E. DEIST ER scnmmme MECHANISM 3 Sheets-Shoe Filed May 2 1926 Fi i .lnmlln INVENTOR. Lljeda Z'cr QM Z1 M A TTORNE Y.

Oct. 2, 192s.j 1,685,942

E. DEIST ER SCREENING MECHANISM I Filed May 24,v 192s 1 s swig-sheet 3 14- t J l4 A TTORNE Y.

Patented Oct. 2, 1928.

. UNITED STATES mm. nnrsrnn, or some wem, mnmiu. A

unomrsm.

Application filed Hay 24, 1926. Serial no. 111,225.

The invention relates to mechanisms for screening ores, eoal, gravel and various other materials. f

. The object of the invention is to provide 6 a durable and eflicient mechanism of few.

parts and one which is economical to construct and o erate.

Another ject is to provide a mechanism in which the screening'medium is supported and vibrated in novel manner.

Another object is to provide a mechanism in which one screening medium or aplurality of mediums may be used, each medium being removable or attachable as a unit.

16- The invention consists of a frame upon which one or a plurality of screening mediums are flexibly supported in tension and means to vibrate the mediums so mounted on the frame supporting the mediums that the '20 vibrating movement, generated by said means is transmitted direct y to the mediums independently of the-frame. v v

The invention is illustrated in the accompanying drawings, in'which Figure 1 is a plan view of a mechanism embod ing the invention, the screening medium being omitted; Fi 2 a side elevational view of the same; Fig. 3 a side elevational view of the mechanism on an enlarged scale; Fig. 4 an end view of the mechanism partly broken away and taken at the feed or upper end thereof; Fig. 5. an elevational view of the discharge or lowr end ofthe mechanism; Fig. ,6 a fractional charge end of the mec anism; Fig. 7 a crosssection on line 77 of Fig. 4; Fig. 8 a crosssection on line 88 of Fig. 5; Fig. 9 an elevational view of the transmitter member taken on line 9-9 of Fig. 10; Fig. 10 a view of the transmitter member taken on line 10-,10 of'Fig. 9; Fig. 11 a plan view ,of one of the supports for t e upper end of the frame; Fig. 12 a central vertical cross-section of the same; Fig. 13 a lan view of one of the screening mediums; ig. 14 a cross-section of the medium on line 1414 of Fig-'13; Fig. 15 a cross-section on line. 15-15 of .Fig. 13; Fig. 169. cross-section on line 1616, of Fig. 13; Fig. 17 a cross-sectional View of one set of the unbalanced members of the vibrating mechanism; Fig. 18 a side elevational view I of one of the said members; Fig. '19 a side elevationalview of the other ofsaid members; Fig. 20 a cross-sectionalview of a modified lan view of the dis form of the tension device for the screening mediums, and Fig. 21 another modified form ofthe said device. 1

Referring to the illustrative embodiment of the invention, 1 and 2 represent two channelirons that form the side members of the These channel 1 main frame of the device.

irons in use rest at their lower ends on a suit- I able support 3. A tie plate or bar 4 is secured 1 by the rivets 5 to, the lower end of the lower flange of each channelby which plate the frame members are tied together, the plate being also bolted to the support 3. An angle iron 6 is secured to the plateand to the lower flangles of both channel irons by one of each of t e sets of rivets 5. This angle iron 6 engages the upper side of the support 3 sov that the lower end of the main frame is held firmly in its inclined position as shown in Fig. 2. The upper or feed end F rests on cushion rings 7 which in turn are held in. their respective positions by means of the socket castings 7 bolted to the lower'flange.

of each channel, and the cushion ring carrier castings 7 suitably secured to the posts or beams 7. This articular arrangement relieves considerably the extreme strains on the screening mediums and tension bolts during the operation of the device and es ecially in the starting and stopping of the device. It also materially reduces the amount of objectionable vibration which would otherwisebe carried into the sub-structure or foundation of the device. 4 Y

quite s arply so that the feed end F is much higher than the discharge end D, the material to be treated being fed adjacent to the end F. In the drawings I illustrate a device having *two screening mediums 8 and 8", each medium being insertable or removable as, a unit. I may adapt the mechanism, however, for any desired number of screening mediums. At the upper end of each medium two bars 9 and '10 are disposed u on opposite sides of the medium and rigi y secured thereto by the bolts 11 and nuts 12, the extremity of the medium being bent over and under the lower bar-'10. At selected points in the bars 9 and 10 clevises or loops 13 are secured to the bars by the bolts 14 and nuts 15 and a bolt 16'is projected loosely through the upright wall In oplerating position the device .is inclined supporting of each clevis or loo and through-an open- I I ingin a Z bar' 17 askets 18 ofleather or 7 other suitable material are disposed upon the projecting outer ends of the bolts 16 and lock nuts 19 hold the bolts in' adjusted position. At this particularv place, however, I prefer to use the arrangement shown in Figure 21 in which a cone-shaped nut 64 fits into the correspondingly coned end of a sleeve 65, mount- I ed in Z bar 17. This cone-shaped nut serves ises on the lower medium and is seated in the to hold the bolt 16 in central osition. The

upper Z bar 17 is secured to t e to side of the spacer castings 21 disposed on t e channel irons and secured thereto by the bolts. 20

and 22 and nuts 2. and 23. The lower Z bar -17 is inverted relatively to the upper Z bar 17 and is suitably bolted or riveted to the lower flange of the channel irons.

At the opposite end of each screening medium are'two bars 24--and 25 similar to the bars 9 and 10 and similarly attached to the screening mediums respectively by the bolts 26 and nuts 27. At oints-in said bars24 and 25 and in longitu inal alinement with the clevisesor loops 13 are secured two loops or clevises 28 by the bolts 29 and nuts 30. A bar 31 is loosely extended through both clevnotchcs 32 formed in the ends of the channel irons. The outer edge of the bar 31 is rounded 0fl" at each clevi's as shown at 31 (Fig. 8) and the adjacent inner wall of the clevis is curved correspondingly so that the clevises may rock more or lesson the bar. The bar 31 for the upper medium is similar to the bar 31 and it is similarly disposed in the clevises on the upper medium. Its. o osite ends are engaged in notches 34 form in the castings 35 that are secured to they upper flanges of the channel irons. Set screws 31 with lock nuts 3l -are mounted at suitable points in the bar 31 to prevent the bar from rattling in the notches 32. The bar 31 for the upper medium is similarly prevented from rattling by the set screws 33 and the screenin mediums at their lower ends.

In or er to vibrate the screening'mediums, I provide the following mechanism: Two chairs 87 are suitably secured to each channel iron, and to, the two chairs on each channel iron I rigidly secure a spring or elastic mam ber 38, preferably made of wood. This sprin member, though ri 'dly secured at each en is free to flex in t e center- At a selected point in each sprin member, I secure a suitable bearing 39, an support in the bearings a shaft '40. Two sets of unbalanced pulleys 41 and 42 are keyed to the shaft'and suitable power may be applied to either pulley of .causin terme late the termination of t e longitudi- 42 is formed with a plurality of key-ways 42 into any one of whichthe key 43 may be inserted. The adjustment of this pulley is accomplished by releasing the set screw 44 therein, sliding the pulley from the key, ro-

tating the pulley to cause the selected key-way 42 to register with the key and then sliding the pulley-v back again onto the key and tightening the set screw, thus changing the relation'of the unbalanced portion of the pulley 41 to the unbalanced portion of the pulley 42. B this adjustment, a refined control of the vibrating movement of the shaft is possible.

A belt 45 is engaged onone'of the pulleys and on a pulley attached to the shaft of the electric motor 45. The motor thereby revolves the shaft, the unbalanced pulleys causing a distinct and positive vibration of the shaft, the bearings supporting the shaft, and of the spring members.

In order to transmit this vibratory movement to the screening mediums, I secure the transmitter members 46 preferably, of the sprin members respectively, the transmitter embers depending res ctively from the spring members. A sprlng 47 is disposed between each transmitter member and the top of the channel below it to prevent sag ing of the spring members, and to intensify t evibrationof said members and of the screenin medium. Thin, flat, flexible bars 48, pre erably made of spring It; the central point,

steel, are secured at one end to the channels and at the other end to the transmitter members respectively. They. serve to' keep the transmitter members in longitudinal alinement. An angle iron 48" is also secured to the transmitter. members and serves to keep them in transverse alinement. 1

Each transmitter member is laterally recessed or pocketed at 50 and 51 to receive respectively the laterall projecting lugs 52 and 53, which are rigidly secured to the angle bars 54' and 55 that are secured to the screenin members respectively and adjacent to the si e edges thereof. Preferably these bars do not extend to the opposite ends of the screens as I have found in practice that the action of the screening mediums is better when the bars terminate at predetermined points, thereby the area of the screemn member in nal bars 54 and 55, and the two bars 9 and 10 and 24 and 25 to be more flexible than the remain ng area of the screening member.

Since the longitudinal bars 54 and 55 are connected to the transmitter members and said members are connected to the spring members, the vibrating movement of the spring members is imparted to the screening mediums.

To uniformly distribute the vibrations over the screening mediums caused by the vibrating bars 54 and 55, I secure the angle irons 56 to the lowcrside of each said medium at points where needed.

Ihavc found in practice that a small portion of the vibrations generated by the unbalanced pulleys is unavoidably carried into the main frame. In order that said vibrations shall not be imparted to the electric motor, I mount the motor upon a board or bar of suitable material 57 and'secure its opposite ends respectively to Z-shaped sheets 58 of rubber, leather, belting or other suitable material.

The sheets are secured to the standards 59 r'espectivcly, that are secured to the channel ironsor are integral with the castings 35. The flexible Z-shaped connections between the motor support and the standardsabsorb any vibration in the standards occasioned by the vibrating parts, and the motor is thereby protected against injury by such vibrations.

Instead of using only the lock nuts 19 on each bolt 16 at the upper end of the screening mediums, Iqmay insert a sleeve 60 (Fig. 20)

in each aperture 61 in the Z bar 17 and provide a recess therein for the reception of one end of'the spring 62, the spring being coiled about the bolt which now extends through the sleeve. The opposite end of the spring is received by a cup 63 mounted on the bolt, the lock nuts 19 then holding the cup 63 in adjusted position. This construction, which I prefer touse when the screening member is of very fine mesh, furnishes a resilient tension on the screening mediums.

I prefer to revolve the unbalanced pulleys at a speed ranging from 2000 to 2100 revolutions per minute, and to so construct the unbalanced pulleys that the amplitude of vibration of the spring members and screening mediums will be approximately of an inch. As previously set out, the amplitude of vibration can be controlledv by a suitable adjustment of the pulleys 41 and 42.

Numerous modifications in the application of the vibrating movement generated in the spring members by the rotating unbalanced pulleys to the screening mediums are possible. I have illustrated but one such application.

What I claim is:

1. A vibrating screen comprising a main frame, a screening medium supported in tension on the frame, spring members mounted on the frame at opposite sides thereof, a transmitter member connected to each spring member and having engagement with the screening medium, a shaft revolubly supported in bearings rigidly secured to both spring members and means on the shaft to cause the is roframe, a screening medium supported in ten-1 -Sl0l'l on the frame, spring members mounted on opposite sides of the frame respectively, a transmitter -member connected to the middle portion of each spring member and'cngagcd to the adjacent side edge of the screening medium, a shaft revolubl mounted at its opposite ends dircctly on t e spring members, an unbalanced member secured to the shaft for causing .the spring members to vibrate and means to drive the shaft.

3. A vibrating screen comprising a main frame, a screening medium supported in-tensionon the frame, spring boards mounted on opposite sides of the frame respectively, transmitter members connected to the spring boards respectively, bars secured to the screening medium and extending along the opposite side edges of the same respectively,

the transmitter membersibeing connected to spectively, bars extending along the opposite sides of the said medium respectively and secured thereto and being parallel to the spring boards, transmitter members secured to the spring boards respectively and secured to the said bars respectively, a shaft revolubly mounted on both spring boardsand an unbalanced pulley secured to the shaft for causing the spring boards to vibrate when the shaft is rotated.

- 5. A vibrating screen consisting of a main frame, a screening'medium mounted in tension on the frame, elastic members mounted on the frame andconnected to the screening medium independenly of the main frame, a shaft revolubly mounted at its opposite ends in bearings fixed to the elastic members,means on the shaft to cause the latter members to vibrate when the shaft is rotated, means to drive the shaft and a support for the drivingmeans flexibly mounted on the main frame.

6. A, vibrating screen comprising a main frame, a screening medium supported in tension on the frame, spring boards mounted on the frame, transmitter means engaging the screening medium and having connection with the spring boards, a shaft revolubly supported on the spring boards and means on the shaft to causethe spring boards to vibrate as the shaft is rotated. I

7. A vibrating screirnconsisting of a main frame, a screening mediun'i supported in tension on the main frame, two sprin boards spring boards and adapted to operatively enmount ed'onithe sidesof the main rame reage "the screening medium whereby the vil0 s ectivel' and extending longitudinally Erations of the spring boards are transmitted t erewit two bearings secured to the sprin to the medium.

boards respectively, a shaft mounted in bot In witness whereof I have hereunto signed bearin s, means on the shaft to cause the my name this 20th day of May, 1926. spring oards to vibrate when the shaft is rotated, and transmitter members secured to the I EMIL DEISTER, 

